UPDATE: Man who was stabbed and killed on Manchester's West Side identified

An autopsy Monday afternoon identified the cause of death as a single stab wound to Gagnon's chest, and the manner of his death has been declared a homicide.

Previous story follows:

A young man was stabbed to death Sunday night in an incident at Black Acres, an area across from Mount Calvary Cemetery on the city's West Side, according to the New Hampshire Attorney General's Office.

Assistant Attorney General Peter Hinckley declined to identify the man, saying his family must be notified first and an autopsy must be completed by the Office of the Chief Medical Examiner. That was expected to take place Monday afternoon.

As of noon Monday, no one was under arrest.

Police went to the Black Acres area at 11:20 p.m. Sunday for a report of a stabbing. Officers located a man suffering a stab wound and tried to help him, but the man died shortly after.

Monday morning, two police cruisers and the police transport van were seen leaving an access road leading to the crime scene. Police said while the investigation is extensive and ongoing, it is still in its preliminary stages although authorities believe they have identified all involved.

Police were first called to the area just after 11 p.m. Sunday on reports of a group of youth running in camouflage gear and pointing lasers. That was followed by a report of possible gunshots.

Police reported finding three abandoned vehicles in the area, one with what appeared to be military equipment inside. By 11:50 p.m., Manchester police were advising officers to not enter the woods in the area, and Goffstown police were helping to establish a perimeter around the scene.

Previous story follows:

MANCHESTER -- The New Hampshire Attorney General said a man died Sunday night after he was stabbed in an incident at Black Acres, an area across from Mount Calvary Cemetery on the city's West Side.

Police went to the area at 11:20 p.m. for a report of a stabbing and tended to a man with an apparent stab wound. The man, whose name police are withholding, died shortly after.

The Office of the Chief Medical Examiner will conduct an autopsy to determine the exact cause and manner of death.

Monday morning, two police cruisers and the police transport van were seen leaving an access road to the crime scene. Police said while the investigation is extensive and ongoing, it is still in its preliminary stages and authorities believe that all of the involved parties to the incident have been identified.

Police were first called to the area just after 11 p.m. Sunday on reports of a group of youth running in camouflage gear and pointing lasers. That was followed by a report of possible gunshots.